Hi Stacy,
I understand your frastration. The circumstances a bit complex for me, I have already checked all possible criteria, but couldn't succeeded. It is not happening with raw template at my end. So it is definitely some conflict that is happening. But I have tried to disable extra plugins to see if it is it, but still issue persist. I have always struggled with the backup though.
It will be a good hint for me if you let me know, what did you changed just prior to the start of the issue?
Lets don't waste your valuable time anymore, but I have shared the issue with my team. Hopefully we will come to an solution soon.
I don't know how to beg more time from you. I'm reaally sorry:(
Best Regards